This one is a bit more symbol heavy, and that's actually the point. The goal here is to represent in somewhat more formal terms the intuition for how backpropagation works in part 3 of the series, hopefully providing some connection between that video and other texts/code that you come across later.

Find the full playlist at http://3b1b.co/neural-networks

Thanks to everyone supporting on Patreon.http://3b1b.co/nn3-thankshttp://3b1b.co/support

For more on backpropagation:http://neuralnetworksanddeeplearning.com/chap2.htmlhttps://github.com/mnielsen/neural-networks-and-deep-learninghttp://colah.github.io/posts/2015-08-Backprop/

Music by Vincent Rubinetti: https://soundcloud.com/vincerubinetti/

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